*: modify the printing of column default expression in `SHOW CREATE T…

…ABLE` and `Restore` (#52940) (#52951) close #52939
pingcap · Apr 29, 2024 · bf84e23 · bf84e23
1 parent 0359bbc
commit bf84e23
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Showing 8 changed files with 6,579 additions and 6,540 deletions.
diff --git a/pkg/ddl/db_integration_test.go b/pkg/ddl/db_integration_test.go
@@ -1592,17 +1592,17 @@ func TestDefaultColumnWithRand(t *testing.T) {
 	tk.MustQuery("show create table t").Check(testkit.Rows(
 		"t CREATE TABLE `t` (\n" +
 			"  `c` int(10) DEFAULT NULL,\n" +
-			"  `c1` int(11) DEFAULT rand()\n" +
+			"  `c1` int(11) DEFAULT (rand())\n" +
 			") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"))
 	tk.MustQuery("show create table t1").Check(testkit.Rows(
 		"t1 CREATE TABLE `t1` (\n" +
 			"  `c` int(11) DEFAULT NULL,\n" +
-			"  `c1` double DEFAULT rand()\n" +
+			"  `c1` double DEFAULT (rand())\n" +
 			") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"))
 	tk.MustQuery("show create table t2").Check(testkit.Rows(
 		"t2 CREATE TABLE `t2` (\n" +
 			"  `c` int(11) DEFAULT NULL,\n" +
-			"  `c1` double DEFAULT rand(1)\n" +
+			"  `c1` double DEFAULT (rand(1))\n" +
 			") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"))
 
 	// use a non-existent function name

diff --git a/pkg/executor/show.go b/pkg/executor/show.go
@@ -1059,12 +1059,19 @@ func constructResultOfShowCreateTable(ctx sessionctx.Context, dbName *model.CISt
 						}
 						buf.WriteString(" DEFAULT NULL")
 					}
-				case "CURRENT_TIMESTAMP", "CURRENT_DATE":
+				case "CURRENT_TIMESTAMP":
 					buf.WriteString(" DEFAULT ")
 					buf.WriteString(defaultValue.(string))
 					if col.GetDecimal() > 0 {
 						fmt.Fprintf(buf, "(%d)", col.GetDecimal())
 					}
+				case "CURRENT_DATE":
+					buf.WriteString(" DEFAULT (")
+					buf.WriteString(defaultValue.(string))
+					if col.GetDecimal() > 0 {
+						fmt.Fprintf(buf, "(%d)", col.GetDecimal())
+					}
+					buf.WriteString(")")
 				default:
 					defaultValStr := fmt.Sprintf("%v", defaultValue)
 					// If column is timestamp, and default value is not current_timestamp, should convert the default value to the current session time zone.
@@ -1077,7 +1084,7 @@ func constructResultOfShowCreateTable(ctx sessionctx.Context, dbName *model.CISt
 					}
 
 					if col.DefaultIsExpr {
-						fmt.Fprintf(buf, " DEFAULT %s", format.OutputFormat(defaultValStr))
+						fmt.Fprintf(buf, " DEFAULT (%s)", format.OutputFormat(defaultValStr))
 					} else {
 						if col.GetType() == mysql.TypeBit {
 							defaultValBinaryLiteral := types.BinaryLiteral(defaultValStr)

diff --git a/pkg/executor/test/showtest/show_test.go b/pkg/executor/test/showtest/show_test.go
@@ -157,7 +157,7 @@ func TestShowCreateTable(t *testing.T) {
 			"  `e` varchar(20) DEFAULT 'cUrrent_tImestamp',\n"+
 			"  `f` datetime(2) DEFAULT CURRENT_TIMESTAMP(2) ON UPDATE CURRENT_TIMESTAMP(2),\n"+
 			"  `g` timestamp(2) DEFAULT CURRENT_TIMESTAMP(2) ON UPDATE CURRENT_TIMESTAMP(2),\n"+
-			"  `h` date DEFAULT CURRENT_DATE\n"+
+			"  `h` date DEFAULT (CURRENT_DATE)\n"+
 			") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin",
 	))
 	tk.MustExec("drop table t")
@@ -318,7 +318,7 @@ func TestShowCreateTable(t *testing.T) {
 	tk.MustQuery("show create table default_sequence").Check(testkit.RowsWithSep("|",
 		""+
 			"default_sequence CREATE TABLE `default_sequence` (\n"+
-			"  `a` int(11) DEFAULT nextval(`test`.`seq`)\n"+
+			"  `a` int(11) DEFAULT (nextval(`test`.`seq`))\n"+
 			") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin",
 	))
 
@@ -489,7 +489,7 @@ func TestShowCreateTable(t *testing.T) {
 	tk.MustExec(`create table t(a bit default (rand()))`)
 	tk.MustQuery(`show create table t`).Check(testkit.RowsWithSep("|", ""+
 		"t CREATE TABLE `t` (\n"+
-		"  `a` bit(1) DEFAULT rand()\n"+
+		"  `a` bit(1) DEFAULT (rand())\n"+
 		") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"))
 
 	tk.MustExec(`drop table if exists t`)

diff --git a/pkg/parser/ast/ddl.go b/pkg/parser/ast/ddl.go
@@ -578,9 +578,21 @@ func (n *ColumnOption) Restore(ctx *format.RestoreCtx) error {
 		ctx.WriteKeyWord("AUTO_INCREMENT")
 	case ColumnOptionDefaultValue:
 		ctx.WriteKeyWord("DEFAULT ")
+		printOuterParentheses := false
+		if funcCallExpr, ok := n.Expr.(*FuncCallExpr); ok {
+			if name := funcCallExpr.FnName.L; name != CurrentTimestamp {
+				printOuterParentheses = true
+			}
+		}
+		if printOuterParentheses {
+			ctx.WritePlain("(")
+		}
 		if err := n.Expr.Restore(ctx); err != nil {
 			return errors.Annotate(err, "An error occurred while splicing ColumnOption DefaultValue Expr")
 		}
+		if printOuterParentheses {
+			ctx.WritePlain(")")
+		}
 	case ColumnOptionUniqKey:
 		ctx.WriteKeyWord("UNIQUE KEY")
 	case ColumnOptionNull: